In this work, the objective was to investigate the decomposition phenomena in methane hydrate (MH) under depressurization condition. A two stages decomposition model is proposed that considers the diffusion phenomena and the cage occupancy, which was applied to analyze the mass transport at the interface of methane hydrate (MH). A heat balance during a decomposition of MH was analyzed with a lumped capacitance model. The temperature of MH was decreased to freezing point during a decomposition of MH even at 2 MPa. Namely, the heat transfer in two stages decomposition model is very important to evaluate the methane gas production rate from MH.